Arizona State senior quarterback Sam Keller is apparently on the verge of quitting the football team after coach Dirk Koetter reversed an earlier decision and named sophomore Rudy Carpenter as the Sun Devils' starter.

Koetter told Keller he was the starter on Friday, but changed his mind on Saturday and told both quarterbacks of his decision.

Keller was not at practice on Sunday night.

"It's simple. I made a mistake on the quarterback situation and I'm changing my mind," Koetter said after Sunday's workout. "We're going to start Rudy Carpenter. I've excused Sam Keller from practice to consider his options."

The East Valley Tribune reported on its Internet site Sunday that a group of players met with Koetter on Saturday to express their preference for Carpenter as the starter.

Koetter did not confirm that meeting.

"Coach Koetter just said, 'Hey, I'm going to do what's best for the team. I'm going to do what the team wants,' " Carpenter said. "I think the decision is going to affect the team in the best way and this is what we're going to do."

Two days ago Keller appeared to emerge as the winner of a fierce competition with Carpenter, who took over starting duties last season when Keller suffered a serious thumb injury.

Keller started the first seven games last season and passed for 2,165 yards and 20 touchdowns , but endured a season-ending injury to his right (passing) thumb trying to stiff-arm Oregon's Haloti Ngata on Oct. 8.

Carpenter stepped in to start the last five games of the season and enjoyed the best freshman season ever for an Arizona State quarterback by passing for 2,273 yards and 17 touchdowns against just two interceptions. His 68.4 completion percentage led the nation.

Both quarterbacks had performed very well in fall camp. The Sun Devils open the season against Northern Arizona on Aug. 31.

"I talked to so many people about this," Koetter said. "This has been weighing heavy on my mind for a long, long time and I'm the one that screwed it up. I have to live with it. I'm also the one who has to fix it."

Keller, who has a redshirt season available, could transfer to another Division I school and sit out a year or go to a Division I-AA school and would be immediately eligible.